On the contrary, they tried to pivot so many times and enter different markets, they bought countless small companies, some big, nothing seemed to stick except the core CPU and datacenter businesses. IIRC mobileye is one somewhat successful venture.
Except they weren't real pivots. Mobile / GPU were x86 centric, foundry half hearted without buying into what needed to be done. Buying a company is the easy bit.
Part of the problem is Intel is addicted to huge margins. Maybe of the areas they have tried to enter are almost commodity products in comparison so it would take some strong leadership to convince everyone to back off those margins for the sake of diversification.
They should have been worried about their process leadership for a long time. IIRC even the vaunted 14nm that they ended up living on for so long was pretty late. That would have had me making backup plans for 10nm but it looked more like leadership just went back to the denial well for years instead. It seemed like they didn't start backport designs until after Zen1 launched to me.
The problem is that Intel has had a defensive strategy for a long time. Yes, they crushed many attempts to breach the x86 moat but failed completely and then gave up attempts to reach beyond that moat. Mobile, foundry, GPUs etc have all seen half-hearted or doomed attempts (plus some bizarre attempts to diversify - McAfee!).
I think that, as Ben essentially says, they put too much faith in never-ending process leadership and the ongoing supremacy of x86. And when that came to an end the moat was dry.